Add documentation on how to contrbute

Author: Nicoretti

docs/src/SUMMARY.md

@@ -17,5 +17,6 @@
 - [Handlebar generator]()
 - [The josh UI]()
 # Contributing
+- [Testing](./contributing/testing.md)
 - [Development tools]()
 - [Tracing]()

docs/src/contributing/dev-tools.md

@@ -0,0 +1,7 @@
+# Dev-Tools
+
+* Nix-Shell
+  - curl
+  - brew trunk
+* Cram
+* Cargo/Rustup

docs/src/contributing/testing.md

@@ -0,0 +1,33 @@
+# Dev Tools
+
+## Nix-Shell
+* [Nix Shell](https://nixos.org/manual/nix/stable/#chap-installation)
+
+
+# Testing
+
+1. Install Nix-Shell
+2. Setup Nix-Shell for testing
+```shell
+nix-shell shell.nix
+```
+3. build 
+   * filter
+   * proxy
+   * trunk build in ui
+
+
+## Unit Tests
+```shell
+cargo test --all
+```
+
+## Integration Tests
+* Build all targets
+* run integration tests
+```shell
+sh run-tests.sh tests/
+```
+
+## UI Tests
+TBD